LeTourneau's Overland Train Mark II was a 572-foot land train built for the United States Army in Longview, Texas, and accepted in February 1962: a control car, two power cars and ten trailers on 54 driven wheels, with four gas turbines making the current.
Narrated with an AI voice. Written with AI help, fact-checked by the channel's editor.
In 1963 the Army tested it in the desert at Yuma, Arizona; its own test report records no stop caused by the ground on either course it drove, yet the tests were ended after two of the sixteen courses it says were tentatively selected and the Army never ordered another. This episode tests three explanations, the helicopter, the money and the machine, against the Army's own accounts, the two Project OTTER reports and the published histories, and follows the one piece that survives, the control car at Yuma Proving Ground.
How this was made
- Research and script. Written with the help of an AI model (Claude, by Anthropic). Each factual claim is checked against the sources, and against a second source where one exists, in two separate AI fact-check passes and then by the channel's editor. Where sources disagree, the narration says so and gives each side.
- Narration. A synthetic voice from ElevenLabs' built-in voice set. It does not imitate anyone in the story.
- Pictures. Photographs and documents are real archival material, credited on screen. Maps, diagrams, timelines and text cards are drawn for the channel by code. No picture in this episode was made by an AI image or video generator.
- Corrections. If you find an error, please comment with a source.
Sources, image credits, chapters and the points where sources disagree are listed under the YouTube version: https://youtu.be/DMhReQ8E6mQ
